Misreporting on Divorce

Today is apparently D-Day here at Freakonomics — the “D” stands for divorce. Along with Hamermesh’s earlier post and this post by Wolfers, there’s one more on the way.

One of the most frustrating things about doing research on families is seeing how often even the simple facts are misreported in the press. And Sue Shellenbarger, writing in this morning’s Wall Street Journal“Work and Family” column, provides yet another example.

First is a clear mistake: “On average, 43 percent of first marriages end in separation or divorce within 15 years, a federal study shows.” I can only assume that she is citing Census Bureau data, showing that 56.9 percent of women married from 1985 to 1989 had reached their 15th anniversary, and from that, inferring that 43.1 percent had divorced or separated within 15 years of marriage.

But as Betsey Stevenson and I noted in this New York Times op-ed, these federal statistics were widely mis-cited. The problem is simply that about one in ten of those who were married from 1985 to 1989 had not reached their 15th anniversary by the time of the 2004 survey, simply because their marriage occurred less than 15 years ago!

In this paper, we re-calculate the equivalent probabilities analyzing only those who had actually been married at least 15 years ago, and find that 33.4 percent of these first marriages ended before their 15th anniversary. Or for those who don’t like our attempted “fix,” I would suggest referring instead to an earlier census analysis (where this problem didn’t occur), which found that 34.8 percent of first marriages ended before their 15th anniversary.

There are two other minor problems with Shellenbarger’s numbers. First, the 43 percent number she cites is based only on the reports of women, while the same federal study notes that the equivalent number for men is a less dramatic 39.4 percent. Applying our corrections lowers these numbers to 35.7 percent for women and 31.2 percent for men, respectively.

And second, some of these couples failed to make it to their 15th anniversary because of death, rather than divorce. Whichever way you look at it, the relevant statistic is surely closer to 33 percent than 43 percent.

The article begins with this motivating fact: “As the national divorce rate plateaus at historically high levels … .”

“Historically high levels”: Yes. “Plateaus”? No way: the divorce rate in the United States is currently at its lowest level in twenty-five years, and has fallen nearly every year since 1979.

The number of divorces per thousand marriages has now fallen by 27 percent since the peak in 1979. The latest data suggest that the divorce rate for 2007 will be even lower still. And our own analysis of the stability of marriages suggests that those married in the 1990′s appear to be less likely to divorce than those married in the 1980′s, who in turn are less likely to divorce than those married in the 1970′s. As such, the divorce rate seems likely to continue to decline for some time yet.

Those interested in a broader assessment of the facts and what may be driving changes in our families may find our Journal of Economic Perspectives paper to be useful. (Also, see my earlier posts at Marginal Revolution: here and here.)

Not debating your statistics. Just trying to understand how there can be a different divorce statistic between men and women (assuming we are only talking about hetrosexual marriage here since you are citing census data). I thought you had to have both to have a marriage.

These sorts of studies just reek of stupidity. No offense, but divorces are just as much a matter of public record as marriages. Why not simply track how many marriages end in divorce? Why bang your head against the wall trying to massage the numbers to tease divorce out of them, when you can just look at the original data? It’s not like we’re trying to discern something hidden–like, say, the number of times per week married couples have sex–from public records of marriage and divorce. Don’t invent statistical methods to guess at something that can be measured directly.